//
//  HSSlideBackViewController.swift
//  HSSlideMenuView
//
//  Created by haisheng huang on 16/3/9.
//  Copyright © 2016年 haisheng huang. All rights reserved.
//
//  只需要继承该类就可以侧滑返回，不需要写任何代码(modal过去的不可以)

import UIKit

class HSSlideBackViewController: UIViewController, UIGestureRecognizerDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        
        // 获取系统自带滑动手势的target对象.
        // Acquisition system with sliding gesture to the target object.
        let target = self.navigationController!.interactivePopGestureRecognizer!.delegate;
        // 创建全屏滑动手势，调用系统自带滑动手势的target的action方法.
        // To create a full-screen slide gestures, sliding gesture to the target system at call the action method.

        let pan = UIPanGestureRecognizer.init(target: target, action: "handleNavigationTransition:")
        // 设置手势代理，拦截手势触发.
        // Set up the gestures agent, intercept gestures trigger.
        pan.delegate = self;
        // 给导航控制器的view添加全屏滑动手势.
        // Add a full-screen slide gestures to view navigation controller.
        self.view.addGestureRecognizer(pan)
        // 禁止使用系统自带的滑动手势.
        // To ban the use of system with sliding gesture.
        self.navigationController!.interactivePopGestureRecognizer!.enabled = false;
        
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    

    /*
    // MARK: - Navigation

    // In a storyboard-based application, you will often want to do a little preparation before navigation
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        // Get the new view controller using segue.destinationViewController.
        // Pass the selected object to the new view controller.
    }
    */

    func gestureRecognizerShouldBegin(gestureRecognizer: UIGestureRecognizer) -> Bool {
        
        // 注意：只有非根控制器才有滑动返回功能，根控制器没有。
        // 判断导航控制器是否只有一个子控制器，如果只有一个子控制器，肯定是根控制器
        // Note: only the root controller is sliding back function, the root controller.
        // To determine whether a navigation controller is only a child controller, if there is only a child controller, must be the root controller.
        if self.childViewControllers.count == 1 {
            // 表示用户在根控制器界面，就不需要触发滑动手势
            // User in the root controller interface, do not need to trigger sliding gesture.
            return false;
        }
        
        return true;
    }
    
    func handleNavigationTransition(sender: UIPanGestureRecognizer) -> Void {
        
        self.navigationController?.popViewControllerAnimated(true)
        
    }
    
}
